Apparatus, system, and method for predicting roaming patterns of mobile devices within wireless networks

ABSTRACT

The disclosed apparatus may include (1) a storage device that maintains information about mobile devices roaming within a wireless network, (2) an AP-prediction unit that (A) determines, based at least in part on the information maintained in the storage device, a number of times that a mobile device has visited a specific AP within the wireless network, (C) generates, based at least in part on the number of times, a score that represents a probability that the specific AP is the next AP visited by the mobile device, and then (D) determines that the score is above a certain threshold, and (3) a profile-distribution unit that provides, in response to the determination that the score is above the certain threshold, the specific AP with a roaming-session profile that facilitates transferring a roaming session of the mobile device to the specific AP. Various other apparatuses, systems, and methods are also disclosed.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.14/664,811 filed 21 Mar. 2015, the disclosure of which is incorporated,in its entirety, by this reference.

BACKGROUND

Mobile devices often roam among various Access Points (APs) within awireless network. For example, a wireless network may include 20 APsthat facilitate connections between mobile devices and the wirelessnetwork. In this example, a mobile device may visit areas covered by 18of those 20 APs over a 1-hour period of time. In doing so, the mobiledevice may establish and/or maintain a network session with the wirelessnetwork by way of the 18 different APs visited over that 1-hour periodof time.

In some scenarios, each of the APs visited by the mobile device may needto obtain a profile and/or context for the mobile device prior tofacilitating a transfer of the mobile device's network session from thelast visited AP. The APs may be able to obtain the mobile device'sprofile and/or context using one or more conventional approaches.Unfortunately, these conventional approaches may have deficiencies thatlead to certain problems (such as high resource consumption,unreliability, and/or delays) within the wireless network.

For example, in one conventional approach, a wireless network may beconfigured to pre-cache each mobile device's profile and/or context ineach of the APs within the wireless network. Unfortunately, thisconventional approach may lead to unnecessarily high memory consumptionand/or processing power usage in the APs.

In another conventional approach, a wireless network may be configuredsuch that a newly visited AP requests the mobile device's profile and/orcontext from the last visited AP. Unfortunately, this conventionalapproach may introduce certain delays into the transfer of the mobiledevice's profile and/or context from one AP to the other, potentiallyresulting in connection loss and/or the need for re-authentication.

In a further conventional approach, a wireless network may be configuredto pre-cache each mobile device's profile and/or context in those APsneighboring the current AP (using, e.g., Radio Resource Management(RRM)). Unfortunately, this conventional approach may require complex,expensive, and/or specialized management tools and/or wirelessarchitectures. Additionally or alternatively, this conventional approachmay fail to take into account whether the mobile devices are even likelyto visit certain neighboring APs. This conventional approach may also besomewhat ineffective in the event that the wireless network includessignal coverage holes.

The instant disclosure, therefore, identifies and addresses a need forapparatuses, systems, and methods for predicting roaming patterns ofmobile devices within wireless networks.

SUMMARY

As will be described in greater detail below, the instant disclosuregenerally relates to apparatuses, systems, and methods for predictingroaming patterns of mobile devices within wireless networks. In oneexample, an apparatus for accomplishing such a task may include astorage device that maintains information about mobile devices roamingwithin a wireless network. The apparatus may also include anAP-prediction unit communicatively coupled to the storage device. TheAP-prediction unit may (1) identify at least one of the mobile devicesroaming within the wireless network, (2) determine, based at least inpart on the information maintained in the storage device, a number oftimes that the mobile device has visited a specific AP within thewireless network, (3) generate, based at least in part on the number oftimes that the mobile device has visited the specific AP, a score thatrepresents a probability that the specific AP is the next AP visited bythe mobile device, and then (4) determine that the score is above acertain threshold. The apparatus may further include aprofile-distribution unit communicatively coupled to the AP-predictionunit. The profile-distribution unit may provide, in response to thedetermination that the score is above the certain threshold, thespecific AP with a roaming-session profile that facilitates transferringa roaming session of the mobile device to the specific AP inanticipation of the specific AP being the next AP visited by the mobiledevice while roaming within the wireless network.

Similarly, a network device incorporating the above-described apparatusmay include a hash table that includes information about mobile devicesroaming within a wireless network. The network device may also includean AP-prediction unit that (1) identifies at least one of the mobiledevices roaming within the wireless network, (2) determines, based atleast in part on the information maintained in the storage device, anumber of times that the mobile device has visited a specific AP withinthe wireless network, (3) generates, based at least in part on thenumber of times that the mobile device has visited the specific AP, ascore that represents a probability that the specific AP is the next APvisited by the mobile device, and then (4) determines that the score isabove a certain threshold. The network device may further include aprofile-distribution unit that provides, in response to thedetermination that the score is above the certain threshold, thespecific AP with a roaming-session profile that facilitates transferringa network connection of the mobile device to the specific AP inanticipation of the specific AP being the next AP visited by the mobiledevice while roaming within the wireless network.

A corresponding method may include (1) identifying at least one mobiledevice roaming within a wireless network, (2) determining a number oftimes that the mobile device has visited a specific AP within thewireless network, (3) generating, based at least in part on the numberof times that the mobile device has visited the specific AP, a scorethat represents a probability that the specific AP is the next APvisited by the mobile device, (4) determining that the score is above acertain threshold, and then in response to the determination that thescore is above the certain threshold, (5) providing the specific AP witha roaming-session profile that facilitates transferring a networkconnection of the mobile device to the specific AP in anticipation ofthe specific AP being the next AP visited by the mobile device whileroaming within the wireless network.

Features from any of the above-mentioned embodiments may be used incombination with one another in accordance with the general principlesdescribed herein. These and other embodiments, features, and advantageswill be more fully understood upon reading the following detaileddescription in conjunction with the accompanying drawings and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate a number of exemplary embodimentsand are a part of the specification. Together with the followingdescription, these drawings demonstrate and explain various principlesof the instant disclosure.

FIG. 1 is a block diagram of an exemplary apparatus for predictingroaming patterns of mobile devices within wireless networks.

FIG. 2 is a block diagram of an exemplary implementation of an apparatusfor predicting roaming patterns of mobile devices within wirelessnetworks.

FIG. 3 is a block diagram of an exemplary network incorporated into animplementation for predicting roaming patterns of mobile devices withinthe network.

FIG. 4 is an illustration of exemplary information about mobile devicesroaming within a wireless network.

FIG. 5 is an illustration of additional exemplary information aboutmobile devices roaming within a wireless network.

FIG. 6 is a flow diagram of an exemplary method for predicting roamingpatterns of mobile devices within wireless networks.

FIG. 7 is a block diagram of an exemplary computing system capable ofimplementing and/or being used in connection with one or more of theembodiments described and/or illustrated herein.

Throughout the drawings, identical reference characters and descriptionsindicate similar, but not necessarily identical, elements. While theexemplary embodiments described herein are susceptible to variousmodifications and alternative forms, specific embodiments have beenshown by way of example in the drawings and will be described in detailherein. However, the exemplary embodiments described herein are notintended to be limited to the particular forms disclosed. Rather, theinstant disclosure covers all modifications, equivalents, andalternatives falling within the scope of the appended claims.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

The present disclosure describes various apparatuses, systems, andmethods for predicting roaming patterns of mobile devices withinwireless networks. As will be explained in greater detail below, bymonitoring and/or tracking the number of times that a mobile device hasvisited certain APs within a wireless network, embodiments of theinstant disclosure may be able to generate a historical representationof the mobile device's roaming pattern within the wireless network. Inaddition, embodiments of the instant disclosure may be able to predict,based at least in part on the historical representation of the mobiledevice's roaming pattern, which of the APs the mobile device will visitnext. The APs that the mobile device is likely to visit next maysometimes be referred to collectively as the “profile neighborhood” or“context neighborhood.” Embodiments of the instant disclosure may thenprovide each AP within the profile neighborhood with a roaming-sessionprofile that facilitates transferring the mobile device's roamingsession to any AP within the profile neighborhood.

When the mobile device first connects to the wireless network and hasyet to establish a history of roaming within the wireless network,embodiments of the instant disclosure may set an initial profileneighborhood for the mobile device that consists of the APs neighboringand/or surrounding the AP first visited by the mobile device. As themobile device begins roaming within the wireless network, embodiments ofthe instant disclosure may modify the initial profile neighborhood toreflect the mobile device's historical roaming pattern instead of merelythe APs neighboring and/or surrounding the AP currently hosting themobile device.

By predicting which APs will be visited next by the mobile device andthen providing each AP within the profile neighborhood with aroaming-session profile that facilitates transferring the mobiledevice's roaming session to any AP within the profile neighborhood,embodiments of the instant disclosure may be able to (1) reduce theamount of memory consumed and/or processing power used by the APs withinthe wireless network, (2) reduce the amount of delay involved intransferring the mobile device's roaming session from one AP to another,(3) decrease the likelihood of connection loss resulting fromtransferring the mobile device's roaming session from one AP to another,(4) mitigate the need for re-authentication in connection withtransferring the mobile device's roaming session from one AP to another,and/or (5) reduce network overhead and/or maintenance costs.

The following will provide, with reference to FIG. 1, examples ofapparatuses that predict roaming patterns of mobile devices withinwireless networks. The discussion corresponding to FIG. 2 will provide adetailed description of exemplary implementations of an apparatus thatpredicts roaming patterns of mobile devices within wireless networks.The discussion corresponding to FIG. 3 will provide a detaileddescription of an exemplary network incorporated into an implementationfor predicting roaming patterns of mobile devices within the network.The discussion corresponding to FIGS. 4 and 5 will provide a detaileddescription of exemplary information about mobile devices roaming withinwireless networks. The discussion corresponding to FIG. 6 will provide adetailed description of an exemplary method for predicting roamingpatterns of mobile devices within wireless networks. Finally, thediscussion corresponding to FIG. 7 will provide numerous examples ofsystems that may include the apparatus shown in FIG. 1.

FIG. 1 shows a block diagram of an exemplary apparatus 100 forpredicting roaming patterns of mobile devices within wireless networks.The term “roaming pattern,” as used herein, generally refers to anypattern or sequence of APs visited by a mobile device within a wirelessnetwork. By predicting the roaming patterns of mobile devices within awireless network, apparatus 100 may be able to predict which APs withinthe wireless network will be visited next by the mobile devices.

As illustrated in FIG. 1, apparatus 100 may include an AP-predictionunit 106 communicatively coupled to a storage device 102. The term“AP-prediction unit,” as used herein, generally refers to any type,form, or portion of physical hardware, circuit, device, and/or processorthat performs certain Input/Output (I/O) operations and/or computingtasks directed to predicting roaming patterns of mobile devices withinwireless networks. In one example, AP-prediction unit 106 may representan integrated circuit whose configuration and/or infrastructure is atleast partially fixed. Additionally or alternatively, AP-prediction unit106 may represent an integrated circuit whose configuration and/orinfrastructure is at least partially variable and/or programmable.Examples of AP-prediction unit 106 include, without limitation,Field-Programmable Gate Arrays (FPGAs), Central Processing Units (CPUs),processors, microprocessors, microcontrollers, Application-SpecificIntegrated Circuits (ASICs), software modules installed on one or moreof the same, portions of one or more of the same, variations of one ormore of the same, combinations of one or more of the same, or any othersuitable AP-prediction unit.

In some examples, storage device 102 may include information 104 aboutmobile devices roaming within a wireless network. In one example,information 104 may be arranged and/or stored in a table (such as a hashtable) within storage device 102. In this example, information 104 maybe indexed by Media Access Control (MAC) addresses that each correspondto a different mobile device roaming with the wireless network. Examplesof storage device 102 include, without limitation, random-access memorydevices, read-only memory devices, solid-state drives, flash drives,disk drives, portions of one or more of the same, variations of one ormore of the same, combinations of one or more of the same, or any othersuitable storage device.

As illustrated in FIG. 1, apparatus 100 may also include aprofile-distribution unit 108 communicatively coupled to AP-predictionunit 106. The term “profile-distribution unit,” as used herein,generally refers to any type, form, or portion of physical hardware,circuit, device, and/or processor that performs certain Input/Output(I/O) operations and/or computing tasks directed to distributingroaming-session profiles for mobile devices to APs within a wirelessnetwork. In one example, profile-distribution unit 108 may represent anintegrated circuit whose configuration and/or infrastructure is at leastpartially fixed. Additionally or alternatively, profile-distributionunit 108 may represent an integrated circuit whose configuration and/orinfrastructure is at least partially variable and/or programmable.Examples of profile-distribution unit 108 include, without limitation,FPGAs, CPUs, processors, microprocessors, microcontrollers, ASICs,software modules installed on one or more of the same, portions of oneor more of the same, variations of one or more of the same, combinationsof one or more of the same, or any other suitable profile-distributionunit.

In some examples, apparatus 100 may include and/or represent all or aportion of a wireless Local Area Network (LAN) controller that managesAPs within a wireless network. Additionally or alternatively, apparatus100 may include and/or represent all or a portion of a master AP thathas been designated and/or assigned to manage other APs within awireless network.

In one example, AP-prediction unit 106 may identify a mobile deviceroaming within a wireless network. In this example, AP-prediction unit106 may determine the number of times that the mobile device has visiteda specific AP within the wireless network. AP-prediction unit 106 mayarrive at this determination based at least in part on information 104stored in storage device 102.

In one example, AP-prediction unit 106 may generate a score based atleast in part on the number of times that the mobile device has visitedthe specific AP. In this example, the score may represent theprobability that the specific AP is the next AP visited by the mobiledevice. Upon generating this score, AP-prediction unit 106 may determinethat the score is above a certain threshold. In response to thedetermination that the score is above that threshold,profile-distribution unit 108 may provide the specific AP with aroaming-session profile that facilitates transferring a roaming sessionof the mobile device to the specific AP. By providing the specific APwith the roaming-session profile in this way, profile-distribution unit108 may ensure that the specific AP is able to seamlessly take over themobile device's roaming session in the event that the specific AP is thenext AP visited by the mobile device while roaming within the wirelessnetwork.

FIG. 2 shows a block diagram of an exemplary implementation 200 ofapparatus 100 for predicting roaming patterns of mobile devices withinwireless networks. As illustrated in FIG. 2, implementation 200 mayinclude apparatus 100 in communication with one or more of APs202(1)-(N) via a network 204. Implementation 200 may also include amobile device 206 that is roaming within network 204. Althoughillustrated as separate entities in FIG. 2, apparatus 100, APs202(1)-(N), and mobile device 206 may all represent and/or be consideredportions of network 204. Additionally or alternatively, apparatus 100and APs 202(1)-(N) may all represent and/or be considered portions ofthe infrastructure and/or architecture of network 204 to which mobiledevice 206 is connected.

The term “network,” as used herein, generally refers to any type or formof medium and/or architecture that facilitates communication or datatransfer. Examples of network 204 include, without limitation, anintranet, a Wide Area Network (WAN), a LAN, a wireless LAN, a PersonalArea Network (PAN), the Internet, a Power Line Communications (PLC)network, a cellular network (e.g., a Global System for MobileCommunications (GSM) network), portions of one or more of the same,variations of one or more of the same, combinations of one or more ofthe same, or any other suitable network. Network 204 may facilitatecommunication or data transfer using wireless and/or wired connections.

The term “access point” and the abbreviation “AP,” as used herein,generally refer to any type or form of computing device that facilitateswireless connections between mobile devices and a network. In oneexample, APs 202(1)-(N) may be positioned and/or arranged throughout aphysical location and/or structure to enable mobile devices to accessnetwork 204 while roaming around the physical location and/or structure.As the mobile devices roam around the physical location and/orstructure, the mobile devices may visit various APs included in APs202(1)-(N). In other words, the mobile devices may establish aconnection to the network through one or more of those APs. Additionallyor alternatively, the APs may transfer the mobile devices' roamingsessions from one to another as the mobile devices roam throughout thephysical location and/or structure.

Each of APs 202(1)-(N) may emit a signal and/or radiation that reachesand/or covers an area of the physical location and/or structure. Asmobile device 206 roams within network 204, mobile device 206 may moveout of an area covered by the signal and/or radiation of one of APs202(1)-(N) and into an area covered by the signal and/or radiation ofanother one of APs 202(1)-(N). As a result, these APs may essentiallypass and/or transfer the roaming session of mobile device 206 from theone to the other such that the connection between mobile device 206 andnetwork 204 goes uninterrupted.

The term “mobile device,” as used herein, generally refers to any typeor form of computing device capable of reading computer-executableinstructions and/or being carried by a user. Examples of mobile device206 include, without limitation, cellular phones, laptops, tablets,Personal Digital Assistants (PDAs), multimedia players, embeddedsystems, wearable devices (e.g., smart watches, smart glasses, etc.),gaming consoles, variations of one or more of the same, combinations ofone or more of the same, or any other suitable mobile device.

As illustrated in FIG. 2, apparatus 100 may also include astorage-maintenance unit 210 communicatively coupled to storage device102. The term “storage-maintenance unit,” as used herein, generallyrefers to any type, form, or portion of physical hardware, circuit,device, and/or processor that performs certain Input/Output (I/O)operations and/or computing tasks directed to maintaining informationabout mobile devices roaming within a wireless network. In one example,storage-maintenance unit 210 may represent an integrated circuit whoseconfiguration and/or infrastructure is at least partially fixed.Additionally or alternatively, storage-maintenance unit 210 mayrepresent an integrated circuit whose configuration and/orinfrastructure is at least partially variable and/or programmable.

Examples of storage-maintenance unit 210 include, without limitation,FPGAs, CPUs, processors, microprocessors, microcontrollers, ASICs,software modules installed on one or more of the same, portions of oneor more of the same, variations of one or more of the same, combinationsof one or more of the same, or any other suitable storage-maintenanceunit. Although illustrated as separate entities in FIG. 2, AP-predictionunit 106, profile-distribution unit 108, and storage-maintenance unit210 may alternatively represent portions of a single unit that predictsroaming patterns of mobile devices within wireless networks.

In one example, storage-maintenance unit 210 may construct a table thatincludes information 104 about the mobile devices roaming within network204. For example, storage-maintenance unit 210 may organize information104 into a hash table stored in storage device 102. Additionally oralternatively, storage-maintenance unit 210 may index information 104included in the hash table by the MAC addresses of the mobile devicesroaming within network 204.

As a specific example, storage-maintenance unit 210 may organizeinformation 104 into a table shown in FIG. 3. By organizing information104 in this way, storage-maintenance unit 210 may ensure thatinformation 104 in FIG. 3 is easily accessible and/or searchable. Asillustrated in FIG. 3, information 104 may identify the MAC addresses ofvarious mobile devices roaming within network 204 (in this example,“32:58:42:61:9C:A2,” “22:F1:A3:93:F4:2E,” “B7:43:33:1A:45:37,”“64:AB:FF:18:C4:01,” and “05:F9:A6:33:FA:21”) and correspondinginformation about those mobile devices (in this example, “Information300,” “Information 302,” “Information 304,” “Information 306,” and“Information 308,” respectively).

Continuing with this example, each of information 300, information 302,information 304, information 306, and information 308 may identify oneor more APs that the mobile devices represented by MAC addresses“32:58:42:61:9C:A2,” “22:F1:A3:93:F4:2E,” “B7:43:33:1A:45:37,”“64:AB:FF:18:C4:01,” and “05:F9:A6:33:FA:21,” respectively, are likelyto visit next. For example, information 304 in FIG. 4 may identify 4different APs previously visited by the mobile device with MAC address“B7:43:33:1A:45:37.” In this example, each AP identified in information304 may have been assigned a score that represents the probability thatthe mobile device with MAC address “B7:43:33:1A:45:37” will visit thatAP next. Moreover, each of the scores assigned to the APs identified ininformation 304 may be above a certain threshold, meaning that themobile device with MAC address “B7:43:33:1A:45:37” is likely to visitone of these APs next (as opposed to visiting one of the other APs next)while roaming within network 204.

As illustrated in FIG. 4, information 304 may identify the MAC addressesof the 4 different APs most likely to be visited next by the mobiledevice with MAC address “B7:43:33:1A:45:37” (in this example,“3C:42:5C:06:24:1A,” “E2:BA:24:19:6B:54,” “16:7B:A5:43:71:3B,” and“45:BA:41:FC:29:B1”), the number of times that the mobile device withMAC address “B7:43:33:1A:45:37” has visited those 4 different APs (inthis example, “4,” “5,” “7,” and “4,” respectively), the scores assignedto those 4 different APs (in this example, “65,” “85,” “80,” and “70,”respectively), and aging timers that indicate the amount of time thathas passed since the mobile device with MAC address “B7:43:33:1A:45:37”last visited those 4 different APs (in this example, “41:30,” “01:30,”“57:04,” and “31:28,” respectively, where the aging timer is formattedin [minutes]:[seconds]).

In one example, AP-prediction unit 106 may identify mobile device 206roaming within network 204. For example, AP-prediction unit 106 maydetect mobile device 206 moving within a physical location and/orstructure covered by network 204. Additionally or alternatively,AP-prediction unit 106 may identify mobile device 206 as being connectedto network 204 by way of AP 202(1).

In one example, AP-prediction unit 106 may determine the number of timesthat mobile device 206 has visited and/or associated with a specific APwithin network 204. For example, AP-prediction unit 106 may accessinformation 104. AP-prediction unit 106 may then determine that mobiledevice 206 has visited and/or associated with AP 202(N) more than 10times. In other words, AP-prediction unit 106 may determine that mobiledevice 206 has established and/or maintained a network connectionthrough AP 202(N) on more than 10 different occasions.

Upon determining the number of times that mobile device 206 has visitedand/or associated with the specific AP, AP-prediction unit 106 maygenerate a score that represents the probability that the specific AP isthe next AP visited by mobile device 206. AP-prediction unit 106 mayapply any of a variety of different algorithms to generate the score.For example, AP-prediction unit 106 may generate a score for AP 202(N)using this formula:

${score} = \left\{ {\begin{matrix}{{1 - {\mathbb{e}}^{- x}}->{{Addition}\mspace{14mu}{Rate}\mspace{14mu}\left( W_{ta} \right)}} \\{{W_{x\; 0} \times \left( {\mathbb{e}}^{- t} \right)}->{{Decay}\mspace{14mu}{Rate}\mspace{14mu}\left( W_{td} \right)}}\end{matrix}.} \right.$

In this example, “x” may represent the number of times that a mobiledevice has visited AP 202(N), “W_(x0)” may represent the value of thescore when the mobile device last roamed away from AP 202(N), and “t”may represent the amount of time that has elapsed since the mobiledevice last roamed away from AP 202(N). Additionally or alternatively,AP-prediction unit 106 may configure information 104 to automaticallygenerate and/or maintain a score for AP 202(N) based at least in part onthat formula.

In some examples, apparatus 100 may maintain and/or keep track ofvarious aging timers. Each of these aging timers may correspond to adifferent AP with respect to a specific mobile device. For example, oneaging timer may correspond to AP 202(N) for mobile device 206. In thisexample, another aging timer may correspond to AP 202(N) for anothermobile device (not necessarily illustrated in FIG. 2).

In some example, aging timers may run (or increase with time) only whenthe corresponding AP is not hosting the mobile device. For example,while mobile device 206 is visiting and/or associated with AP 202(N),the aging timer corresponding to AP 202(N) for mobile device 206 mayremain stopped and/or reset. In contrast, while mobile device 206 isroaming elsewhere within network 204 and is not associated with AP202(N), the aging timer corresponding to AP 202(N) for mobile device 206may be running (or increasing with time).

In some examples, aging timers may stop and/or reset once the mobiledevice re-visits and/or re-associates with the corresponding AP. Forexample, when mobile device 206 re-visits and/or re-associates with AP202(N), apparatus 100 may stop and/or reset the aging timercorresponding to AP 202(N) for mobile device 206. Accordingly, thisaging timer may cause the corresponding score to decay and/or decrementonly while mobile device 206 is not visiting and/or associating with AP202(N).

Upon generating the score, AP-prediction unit 106 may determine that thescore is above a certain threshold. For example, AP-prediction unit 106may determine that the score for AP 202(N) is above a threshold value of“60.” In one example, this threshold may be arbitrarily fixed at aspecific value. In another example, this threshold may vary based atleast in part on the scores for other APs relative to mobile device 206(e.g., such that information 304 always identifies the 4 APs most likelyto be visited next by mobile device 206).

In response to the determination that the score is above the threshold,profile-distribution unit 108 may provide AP 202(N) with aroaming-session profile that facilitates transferring the roamingsession of mobile device 206 to AP 202(N). The term “roaming-sessionprofile,” as used herein, generally refers to any type or form of data,information, keys, and/or context that enables an AP to provide networkaccess to a mobile device that has been authenticated previously byanother AP. For example, in the event that AP 202(1) has previouslyauthenticated mobile device 206, AP 202(N) may skip the authenticationprocess for mobile device 206 based at least in part on theroaming-session profile. In this example, the authentication process mayinclude and/or represent Institute of Electrical and ElectronicsEngineers (IEEE) 802.1X authentication.

In one example, profile-distribution unit 108 may provide AP 202(N) withthe roaming-session profile by directing AP 202(1) to send an instanceof the roaming-session profile to AP 202(N). Additionally oralternatively, profile-distribution unit 108 may provide AP 202(N) withthe roaming-session profile by sending an instance of theroaming-session profile to AP 202(N) from apparatus 100.

In one example, the roaming-session profile may include one or moreroaming keys, unique network keys, encryption keys, and/or othersecurity parameters that indicate how to encode network traffic destinedfor mobile device 206 during the roaming session. For example, theroaming-session profile may include a Pairwise Master Key (PMK) used toencode network traffic destined for mobile device 206 during the roamingsession. Additionally or alternatively, the roaming-session profile mayinclude one or more multicast and/or broadcast keys. The roaming-sessionprofile may also include one or more unicast and/or mapping keys.

In some examples, the size of the roaming-session profile may varydepending on the type of roaming session of mobile device 206 and/or thetype(s) of services applied to the network traffic transferred to and/orfrom mobile device 206 during the roaming session. For example, network204 may apply certain security services to network traffic originatingfrom and/or destined for mobile device 206. In this example, the size ofroaming-session profile may remain relatively small.

However, in another example, network 204 may apply Deep PacketInspection (DPI) and/or firewall services to network traffic originatingfrom and/or destined for mobile device 206. In this example, the size ofroaming-session profile may become relatively large. As a result, toavoid reaching the scalability and/or resource limitations of theindividual APs, network 204 may distribute the roaming-session profilefor mobile device 206 to only those APs that are most likely to bevisited next by mobile device 206. In other words, network 204 maydistribute the roaming-session profile for mobile device 206 to onlythose APs whose scores with respect to mobile device 206 are above thethreshold.

As a specific example, network 204 in FIG. 5 may include APs202(1)-202(12). As illustrated in FIG. 5, each of APs 202(1)-(12) mayemit a signal and/or radiation that reaches and/or covers a certain areaor space. For example, APs 202(1), 202(2), 202(11), and 202(12) may eachemit a signal and/or radiation that reaches the perimeter represented bysignal coverage areas 502(1), 502(2), 502(11), and 502(12),respectively, in FIG. 5.

As illustrated in FIG. 5, mobile devices 206(1)-(3) may be roamingaround a physical location and/or structure covered by network 204. Inan effort to distribute the respectively roaming-session profiles ofmobile devices 206(1)-(3) to only those APs that are most likely to bevisited next by mobile devices 206(1)-(3), apparatus 100 (notillustrated in FIG. 5) may maintain information 104 about mobile devices206(1)-(3) in storage device 102. In addition, apparatus 100 maydetermine the number of times that mobile device 206(1)-(3) have visitedAPs 202(1)-(N) within network 204 based at least in part on information104. For example, apparatus 100 may determine that mobile device 206(1)has visited each of APs 202(1)-(4) four times within the last hour, eachof APs 202(5)-(8) two times within the last hour, and each of APs202(9)-(12) zero times within the last hour.

Continuing with this example, apparatus 100 may determine that mobiledevice 206(2) has visited each of APs 202(1)-(5) one time within thelast hour, each of APs 202(6)-(8) four times within the last hour, andeach of APs 202(9)-(12) one time within the last hour. Additionally oralternatively, apparatus 100 may determine that mobile device 206(3) hasvisited each of APs 202(1)-(6) zero times within the last hour, each ofAPs 202(7)-(9) three times within the last hour, and each of APs202(10)-(12) five times within the last hour.

Apparatus 100 may then generate, for each of APs 202(1)-(12), scoresthat represent the probability that the AP in question will be the nextAP visited by mobile devices 206(1)-(3). For example, apparatus 100 maygenerate a score of “75” for AP 202(4) with respect to mobile device206(1). In this example, the score of “75” may represent the probabilitythat AP 202(4) is the next AP visited by mobile device 206(1) whileroaming within network 204.

As a similar example, apparatus 100 may generate a score of “30” for AP202(4) with respect to mobile device 206(2). In this example, the scoreof “30” may represent the probability that AP 202(4) is the next APvisited by mobile device 206(2) while roaming within network 204. Asanother similar example, apparatus 100 may generate a score of “0” forAP 202(4) with respect to mobile device 206(3). In this example, thescore of “0” may represent the probability that AP 202(4) is the next APvisited by mobile device 206(3) while roaming within network 204.

In this example, network 204 may maintain a threshold value of “60” fordetermining whether an AP is likely to be visited next by a mobiledevice. Accordingly, apparatus 100 may determine that the score of “75”for AP 202(4) with respect to mobile device 206(1) is above thethreshold value of “60.” In other words, mobile device 206(1) may beconsidered likely to visit AP 202(4) next while roaming within network204. As a result, apparatus 100 may provide AP 202(4) with theroaming-session profile of mobile device 206(1) in anticipation ofmobile device 206(1) potentially visiting AP 202(4) next.

Similarly, apparatus 100 may determine that the score of “30” for AP202(4) with respect to mobile device 206(2) is below the threshold valueof “60.” In other words, mobile device 206(2) may be considered unlikelyto visit AP 202(4) next while roaming within network 204. As a result,apparatus 100 may refrain from providing AP 202(4) with theroaming-session profile of mobile device 206(2) in an effort to avoidconsuming unnecessary memory and/or processing power on AP 202(4).

Additionally or alternatively, apparatus 100 may determine that thescore of “0” for AP 202(4) with respect to mobile device 206(3) is belowthe threshold value of “60.” In other words, mobile device 206(3) may beconsidered unlikely to visit AP 202(4) next while roaming within network204. As a result, apparatus 100 may refrain from providing AP 202(4)with the roaming-session profile of mobile device 206(3) in an effort toavoid consuming unnecessary memory and/or processing power on AP 202(4).

In some examples, storage-maintenance unit 210 may update information104 as mobile devices 206(1)-(3) roam within network 204. For example,mobile device 206(1) may visit AP 202(4) while roaming within network204. Once AP 202(4) assumes the roaming session of mobile device 206(1),AP 202(4) may send a notification indicating the same to apparatus 100.

As the notification arrives at apparatus 100, storage-maintenance unit210 may receive the notification and then update information 104 toaccount for the recent visit of mobile device 206(1) to AP 202(4). Forexample, storage-maintenance unit 210 may reset and/or restart the agingtimer for AP 202(4) with respect to mobile device 206(1). By resettingand/or restarting the aging timer in this way, storage-maintenance unit210 may essentially reset and/or restart any decay and/or decrementapplied to the corresponding score for AP 202(4).

In another example, mobile device 206(3) may visit AP 202(11) whileroaming within network 204. Once AP 202(11) assumes the roaming sessionof mobile device 206(3), AP 202(11) may send a notification indicatingthe same to apparatus 100.

As the notification arrives at apparatus 100, storage-maintenance unit210 may receive the notification and then update information 104 toaccount for the recent visit of mobile device 206(3) to AP 202(11). Forexample, storage-maintenance unit 210 may reset and/or restart the agingtimer for AP 202(11) with respect to mobile device 206(3). By resettingand/or restarting the aging timer in this way, storage-maintenance unit210 may essentially reset and/or restart any decay and/or decrementapplied to the corresponding score for AP 202(11).

In a further example, storage-maintenance unit 210 may determine thatmobile device 206(1) has not visited AP 202(9) within a certain amountof time. For example, storage-maintenance unit 210 may determine thatmobile device 206(1) has not visited AP 202(9) within the last two hoursbased at least in part on the aging timer for AP 202(9). In response tothis determination, storage-maintenance unit 210 may remove an entrycorresponding to AP 202(9) from information 104 and/or the profileneighborhood for mobile device 206(1).

In some examples, the scores for APs 202(1)-(12) may decrease as theaging timers for APs 202(1)-(N) increase. For example,storage-maintenance unit 210 may configure information 104 such that thescores for AP 202(7) with respect to mobile devices 206(1)-(3) decreaseas the aging timers for AP 202(7) with respect to mobile devices206(1)-(3) increase. Additionally or alternatively, AP-prediction unit106 may detect an increase in the amount of time since mobile device206(2) last visited AP 202(7) based at least in part on thecorresponding aging timer for AP 202(7). AP-prediction unit 106 may thendecrement the score for AP 202(7) with respect to mobile device 206(2)to account for the increase in the amount of time since mobile device206(2) last visited AP 202(7).

In some examples, AP-prediction unit 106 may generate the scores for APs202(1)-(12) based at least in part on the roaming patterns of mobiledevices 206(1)-(3). For example, AP-prediction unit 106 may generate arepresentation of a roaming pattern for mobile device 206(1) based atleast in part on the number of times that mobile device 206(1) hasvisited APs 202(1)-(12). AP-prediction unit 106 may then generate and/ormodify a score for each of APs 202(1)-(12) with respect to mobile device206(1) based at least in part on the roaming pattern for mobile device206(1).

In some examples, a mobile device may roam to an AP that is not includedin the mobile device's profile neighborhood. For example, mobile device206(1) may roam to AP 202(10) from AP 202(7) even though mobile device206(1) had not visited AP 202(10) at all within the last hour. Since, inthis example, AP 202(10) is not be included in the mobile device'sprofile neighborhood, AP 202(10) may not yet have access to theroaming-session profile of mobile device 206(1). As a result, AP 202(10)may request and obtain the roaming-session profile of mobile device206(1) from AP 202(7), and AP-prediction unit 106 may add AP 202(10) tothe profile neighborhood of mobile device 206(1).

FIG. 6 is a flow diagram of an exemplary method 600 for predictingroaming patterns of mobile devices within wireless networks. Method 600may include the step of identifying at least one mobile device roamingwithin a wireless network (610). This identifying step may be performedin a variety of ways. For example, AP-prediction unit 106 may, as partof a wireless LAN controller or master AP, identify mobile device 206roaming within network 204 by receiving a notification indicating thatmobile device 206 is attempting to associate with one or more of APs202(1)-(N). In another example, AP-prediction unit 106 may identifymobile device 206 roaming within network 204 by analyzing information104 maintained in storage device 102.

Returning to FIG. 6, method 600 may also include the step of determininga number of times that the mobile device has visited a specific APwithin the wireless network (620). This determining step may beperformed in a variety of ways. For example, AP-prediction unit 106 may,as part of the wireless LAN or master AP, determine the number of timesthat mobile device 206 has visited AP 202(1) within network 204 byanalyzing information 104 maintained in storage device 102. In thisexample, storage-maintenance unit 210 may, as part of the wireless LANor master AP, update information 104 on an as-needed basis to ensurethat information 104 reflects the current number of times that mobiledevice has visited AP 202(1).

Returning to FIG. 6, method 600 may additionally include the step ofgenerating a score that represents a probability that the specific AP isthe next AP visited by the mobile device based at least in part on thenumber of times that the mobile device has visited the specific AP(630). This generating step may be performed in a variety of ways. Forexample, AP-prediction unit 106 may, as part of the wireless LAN ormaster AP, generate a score that represents the probability that AP202(1) will be the next AP visited by mobile device 206 based at leastin part on the number of times that mobile device 206 has previouslyvisited AP 202(1). In another example, AP-prediction unit 106 mayconfigure information 104 to automatically generate and/or maintain sucha score for AP 202(1) based at least in part on a mathematical formulathat accounts for the number of times that mobile device 206 haspreviously visited AP 202(1).

Returning to FIG. 6, method 600 may further include the step ofdetermining that the score is above a certain threshold (640). Thisdetermining step may be performed in a variety of ways. For example,AP-prediction unit 106 may, as part of the wireless LAN or master AP,compare the score that represents the probability that AP 202(1) will bethe next AP visited by mobile device 206 with a certain threshold.AP-prediction unit 106 may then determine that the score is above thethreshold based at least in part on this comparison.

Returning to FIG. 6, method 600 may finally include the step ofproviding the specific AP with a roaming-session profile thatfacilitates transferring a roaming session of the mobile device to thespecific AP in anticipation of the specific AP being the next AP visitedby the mobile device while roaming with the wireless network (650). Thisproviding step may be performed in a variety of ways. For example,AP-prediction unit 106 may, as part of the wireless LAN or master AP,provide AP 202(1) with a roaming-session profile by directing the APwith which mobile device 206 is currently associated to send an instanceof the roaming-session profile to AP 202(1). In another example,AP-prediction unit 106 may provide AP 202(1) with the roaming-sessionprofile by sending an instance of the roaming-session profile to AP202(1) from apparatus 100.

FIG. 7 is a block diagram of an exemplary computing system 700 capableof implementing and/or being used in connection with one or more of theembodiments described and/or illustrated herein. In some embodiments,all or a portion of computing system 700 may perform and/or be a meansfor performing, either alone or in combination with other elements, oneor more of the steps described in connection with FIG. 5. All or aportion of computing system 700 may also perform and/or be a means forperforming and/or implementing any other steps, methods, or processesdescribed and/or illustrated herein. In one example, computing system700 may include apparatus 100 from FIG. 1.

Computing system 700 broadly represents any type or form of electricalload, including a single or multi-processor computing device or systemcapable of executing computer-readable instructions. Examples ofcomputing system 700 include, without limitation, network devices (e.g.,wireless WLAN controllers, master APs, etc.), workstations, laptops,client-side terminals, servers, distributed computing systems, mobiledevices, network switches, network routers (e.g., backbone routers, edgerouters, core routers, mobile service routers, broadband routers, etc.),network appliances (e.g., network security appliances, network controlappliances, network timing appliances, SSL VPN (Secure Sockets LayerVirtual Private Network) appliances, etc.), network controllers,gateways (e.g., service gateways, mobile packet gateways, multi-accessgateways, security gateways, etc.), and/or any other type or form ofcomputing system or device.

Computing system 700 may be programmed, configured, and/or otherwisedesigned to comply with one or more networking protocols. According tocertain embodiments, computing system 700 may be designed to work withprotocols of one or more layers of the Open Systems Interconnection(OSI) reference model, such as a physical layer protocol, a link layerprotocol, a network layer protocol, a transport layer protocol, asession layer protocol, a presentation layer protocol, and/or anapplication layer protocol. For example, computing system 700 mayinclude a network device configured according to a Universal Serial Bus(USB) protocol, an Institute of Electrical and Electronics Engineers(IEEE) 1394 protocol, an Ethernet protocol, a T1 protocol, a SynchronousOptical Networking (SONET) protocol, a Synchronous Digital Hierarchy(SDH) protocol, an Integrated Services Digital Network (ISDN) protocol,an Asynchronous Transfer Mode (ATM) protocol, a Point-to-Point Protocol(PPP), a Point-to-Point Protocol over Ethernet (PPPoE), a Point-to-PointProtocol over ATM (PPPoA), a Bluetooth protocol, an IEEE 802.XXprotocol, a frame relay protocol, a token ring protocol, a spanning treeprotocol, and/or any other suitable protocol.

Computing system 700 may include various network and/or computingcomponents. For example, computing system 700 may include at least oneprocessor 714 and a system memory 716. Processor 714 generallyrepresents any type or form of processing unit capable of processingdata or interpreting and executing instructions. For example, processor714 may represent an application-specific integrated circuit (ASIC), asystem on a chip (e.g., a network processor), a hardware accelerator, ageneral purpose processor, and/or any other suitable processing element.

Processor 714 may process data according to one or more of thenetworking protocols discussed above. For example, processor 714 mayexecute or implement a portion of a protocol stack, may process packets,may perform memory operations (e.g., queuing packets for laterprocessing), may execute end-user applications, and/or may perform anyother processing tasks.

System memory 716 generally represents any type or form of volatile ornon-volatile storage device or medium capable of storing data and/orother computer-readable instructions. Examples of system memory 716include, without limitation, Random Access Memory (RAM), Read OnlyMemory (ROM), flash memory, or any other suitable memory device.Although not required, in certain embodiments computing system 700 mayinclude both a volatile memory unit (such as, for example, system memory716) and a non-volatile storage device (such as, for example, primarystorage device 732, as described in detail below). System memory 716 maybe implemented as shared memory and/or distributed memory in a networkdevice. Furthermore, system memory 716 may store packets and/or otherinformation used in networking operations.

In certain embodiments, exemplary computing system 700 may also includeone or more components or elements in addition to processor 714 andsystem memory 716. For example, as illustrated in FIG. 7, computingsystem 700 may include a memory controller 718, an Input/Output (I/O)controller 720, and a communication interface 722, each of which may beinterconnected via communication infrastructure 712. Communicationinfrastructure 712 generally represents any type or form ofinfrastructure capable of facilitating communication between one or morecomponents of a computing device. Examples of communicationinfrastructure 712 include, without limitation, a communication bus(such as a Serial ATA (SATA), an Industry Standard Architecture (ISA), aPeripheral Component Interconnect (PCI), a PCI Express (PCIe), and/orany other suitable bus), and a network.

Memory controller 718 generally represents any type or form of devicecapable of handling memory or data or controlling communication betweenone or more components of computing system 700. For example, in certainembodiments memory controller 718 may control communication betweenprocessor 714, system memory 716, and I/O controller 720 viacommunication infrastructure 712. In some embodiments, memory controller718 may include a Direct Memory Access (DMA) unit that may transfer data(e.g., packets) to or from a link adapter.

I/O controller 720 generally represents any type or form of device ormodule capable of coordinating and/or controlling the input and outputfunctions of a computing device. For example, in certain embodiments I/Ocontroller 720 may control or facilitate transfer of data between one ormore elements of computing system 700, such as processor 714, systemmemory 716, communication interface 722, and storage interface 730.

Communication interface 722 broadly represents any type or form ofcommunication device or adapter capable of facilitating communicationbetween exemplary computing system 700 and one or more additionaldevices. For example, in certain embodiments communication interface 722may facilitate communication between computing system 700 and a privateor public network including additional computing systems. Examples ofcommunication interface 722 include, without limitation, a link adapter,a wired network interface (such as a network interface card), a wirelessnetwork interface (such as a wireless network interface card), and anyother suitable interface. In at least one embodiment, communicationinterface 722 may provide a direct connection to a remote server via adirect link to a network, such as the Internet. Communication interface722 may also indirectly provide such a connection through, for example,a local area network (such as an Ethernet network), a personal areanetwork, a wide area network, a private network (e.g., a virtual privatenetwork), a telephone or cable network, a cellular telephone connection,a satellite data connection, or any other suitable connection.

In certain embodiments, communication interface 722 may also represent ahost adapter configured to facilitate communication between computingsystem 700 and one or more additional network or storage devices via anexternal bus or communications channel. Examples of host adaptersinclude, without limitation, Small Computer System Interface (SCSI) hostadapters, Universal Serial Bus (USB) host adapters, IEEE 1394 hostadapters, Advanced Technology Attachment (ATA), Parallel ATA (PATA),Serial ATA (SATA), and External SATA (eSATA) host adapters, FibreChannel interface adapters, Ethernet adapters, or the like.Communication interface 722 may also enable computing system 700 toengage in distributed or remote computing. For example, communicationinterface 722 may receive instructions from a remote device or sendinstructions to a remote device for execution.

As illustrated in FIG. 7, exemplary computing system 700 may alsoinclude a primary storage device 732 and/or a backup storage device 734coupled to communication infrastructure 712 via a storage interface 730.Storage devices 732 and 734 generally represent any type or form ofstorage device or medium capable of storing data and/or othercomputer-readable instructions. For example, storage devices 732 and 734may represent a magnetic disk drive (e.g., a so-called hard drive), asolid state drive, a floppy disk drive, a magnetic tape drive, anoptical disk drive, a flash drive, or the like. Storage interface 730generally represents any type or form of interface or device fortransferring data between storage devices 732 and 734 and othercomponents of computing system 700.

In certain embodiments, storage devices 732 and 734 may be configured toread from and/or write to a removable storage unit configured to storecomputer software, data, or other computer-readable information.Examples of suitable removable storage units include, withoutlimitation, a floppy disk, a magnetic tape, an optical disk, a flashmemory device, or the like. Storage devices 732 and 734 may also includeother similar structures or devices for allowing computer software,data, or other computer-readable instructions to be loaded intocomputing system 700. For example, storage devices 732 and 734 may beconfigured to read and write software, data, or other computer-readableinformation. Storage devices 732 and 734 may be a part of computingsystem 700 or may be separate devices accessed through other interfacesystems.

Many other devices or subsystems may be connected to computing system700. Conversely, all of the components and devices illustrated in FIG. 7need not be present to practice the embodiments described and/orillustrated herein. The devices and subsystems referenced above may alsobe interconnected in different ways from those shown in FIG. 7.Computing system 700 may also employ any number of software, firmware,and/or hardware configurations. For example, one or more of theexemplary embodiments disclosed herein may be encoded as a computerprogram (also referred to as computer software, software applications,computer-readable instructions, or computer control logic) on acomputer-readable medium. The term “computer-readable medium” generallyrefers to any form of device, carrier, or medium capable of storing orcarrying computer-readable instructions. Examples of computer-readablemedia include, without limitation, transmission-type media, such ascarrier waves, and non-transitory-type media, such as magnetic-storagemedia (e.g., hard disk drives and floppy disks), optical-storage media(e.g., Compact Disks (CDs) and Digital Video Disks (DVDs)),electronic-storage media (e.g., solid-state drives and flash media), andother distribution systems.

While the foregoing disclosure sets forth various embodiments usingspecific block diagrams, flowcharts, and examples, each block diagramcomponent, flowchart step, operation, and/or component described and/orillustrated herein may be implemented, individually and/or collectively,using a wide range of hardware, software, or firmware (or anycombination thereof) configurations. In addition, any disclosure ofcomponents contained within other components should be consideredexemplary in nature since many other architectures can be implemented toachieve the same functionality.

In some examples, all or a portion of apparatus 100 in FIG. 1 mayrepresent portions of a cloud-computing or network-based environment.Cloud-computing and network-based environments may provide variousservices and applications via the Internet. These cloud-computing andnetwork-based services (e.g., software as a service, platform as aservice, infrastructure as a service, etc.) may be accessible through aweb browser or other remote interface. Various functions describedherein may also provide network switching capabilities, gateway accesscapabilities, network security functions, content caching and deliveryservices for a network, network control services, and/or and othernetworking functionality.

In addition, one or more of the modules described herein may transformdata, physical devices, and/or representations of physical devices fromone form to another. For example, one or more of the modules recitedherein may receive data to be transformed, transform the data into ascore, output a result of the transformation to determine whether an APis likely to be visited next by a mobile device, use the result of thetransformation to predict a roaming pattern of the mobile device, andstore the result of the transformation to determine which APs are toreceive a roaming-session profile for the mobile device. Additionally oralternatively, one or more of the modules recited herein may transform aprocessor, volatile memory, non-volatile memory, and/or any otherportion of a physical computing device from one form to another byexecuting on the computing device, storing data on the computing device,and/or otherwise interacting with the computing device.

The process parameters and sequence of the steps described and/orillustrated herein are given by way of example only and can be varied asdesired. For example, while the steps illustrated and/or describedherein may be shown or discussed in a particular order, these steps donot necessarily need to be performed in the order illustrated ordiscussed. The various exemplary methods described and/or illustratedherein may also omit one or more of the steps described or illustratedherein or include additional steps in addition to those disclosed.

The preceding description has been provided to enable others skilled inthe art to best utilize various aspects of the exemplary embodimentsdisclosed herein. This exemplary description is not intended to beexhaustive or to be limited to any precise form disclosed. Manymodifications and variations are possible without departing from thespirit and scope of the instant disclosure. The embodiments disclosedherein should be considered in all respects illustrative and notrestrictive. Reference should be made to the appended claims and theirequivalents in determining the scope of the instant disclosure.

Unless otherwise noted, the terms “connected to” and “coupled to” (andtheir derivatives), as used in the specification and claims, are to beconstrued as permitting both direct and indirect (i.e., via otherelements or components) connection. In addition, the terms “a” or “an,”as used in the specification and claims, are to be construed as meaning“at least one of.” Finally, for ease of use, the terms “including” and“having” (and their derivatives), as used in the specification andclaims, are interchangeable with and have the same meaning as the word“comprising.”

What is claimed is:
 1. An apparatus comprising: a storage device thatmaintains information about mobile devices roaming within a wirelessnetwork; an AP-prediction unit communicatively coupled to the storagedevice, wherein the AP-prediction unit: determines, based at least inpart on the information maintained in the storage device, a number oftimes that a mobile device has visited a specific Access Point (AP)within the wireless network; generates, based at least in part on thenumber of times that the mobile device has visited the specific AP, aprobability that the specific AP is the next AP visited by the mobiledevice; and determines that the probability is above a certainthreshold; and a profile-distribution unit that provides, in response tothe determination that the probability is above the certain threshold,the specific AP with a roaming-session profile that: facilitatestransferring a roaming session of the mobile device to the specific APin anticipation of the specific AP being the next AP visited by themobile device while roaming within the wireless network; and enables thespecific AP to provide network access to the mobile device due at leastin part to the mobile device having been authenticated previously by anadditional AP.
 2. The apparatus of claim 1, further comprising astorage-maintenance unit communicatively coupled to the storage device,wherein the storage-maintenance unit: constructs a table that includesthe information about the mobile devices roaming within the wirelessnetwork; and indexes the information included in the table by MediaAccess Control (MAC) addresses that each correspond to a differentmobile device roaming within the wireless network.
 3. The apparatus ofclaim 2, wherein the storage-maintenance unit further: receives, fromthe specific AP, one or more notifications indicating that one or moreof the mobile devices roaming within the wireless network have recentlyvisited the specific AP; and updating the information included in thetable based at least in part on the notifications received from thespecific AP.
 4. The apparatus of claim 2, wherein thestorage-maintenance unit further: receives, from another AP within thewireless network, a notification indicating that the mobile device hasrecently visited the other AP; and updating the information included inthe table based at least in part on the notification indicating that themobile device has recently visited the other AP.
 5. The apparatus ofclaim 2, wherein the information about the mobile devices comprisesinformation that identifies a set of APs whose probabilities of themobile device visiting next are above the certain threshold.
 6. Theapparatus of claim 5, wherein the information about the mobile devicesfurther comprises information that identifies, for each individual APwithin the set of APs: a MAC address of the individual AP; a number oftimes that the mobile device has visited the individual AP; aprobability that the individual AP is the next AP visited by the mobiledevice; and an aging timer that represents an amount of time since themobile device last visited the individual AP.
 7. The apparatus of claim6, wherein the storage-maintenance unit: determines, based at least inpart on the aging timer, that the mobile device has not visited theindividual AP within a certain amount of time; and removes an entrycorresponding to the individual AP from the information in response todetermining that the mobile device has not visited the individual APwithin the certain amount of time.
 8. The apparatus of claim 6, whereinthe AP-prediction unit: detects, based at least in part on the agingtimer, an increase in the amount of time since the mobile device lastvisited the individual AP; and decrements the probability that theindividual AP is the next AP visited by the mobile device due at leastin part to the increase in the amount of time since the mobile devicelast visited the individual AP.
 9. The apparatus of claim 1, wherein theAP-prediction unit determines the number of times that the mobile devicehas visited the specific AP by determining a number of times that themobile device has established a network connection through the specificAP.
 10. The apparatus of claim 1, wherein the AP-prediction unit:determines the number of times that the mobile device has visited thespecific AP by generating, based at least in part on the number of timesthat the mobile device has visited the specific AP, a representation ofa roaming pattern of the mobile device within the wireless network; andgenerates, based at least in part on the representation of the roamingpattern of the mobile device, the probability that the specific AP isthe next AP visited by the mobile device.
 11. A network devicecomprising: a hash table that includes information about mobile devicesroaming within a wireless network; and an AP-prediction unit that:determines, based at least in part on the information included in thehash table, a number of times that a mobile device has visited aspecific Access Point (AP) within the wireless network; generates, basedat least in part on the number of times that the mobile device hasvisited the specific AP, a probability that the specific AP is the nextAP visited by the mobile device; and determines that the probability isabove a certain threshold; and a profile-distribution unit thatprovides, in response to the determination that the probability is abovethe certain threshold, the specific AP with a roaming-session profilethat: facilitates transferring a roaming session of the mobile device tothe specific AP in anticipation of the specific AP being the next APvisited by the mobile device while roaming within the wireless network;and enables the specific AP to provide network access to the mobiledevice due at least in part to the mobile device having beenauthenticated previously by an additional AP.
 12. The network device ofclaim 11, further comprising: a storage device that stores the hashtable; and a storage-maintenance unit communicatively coupled to thestorage device, wherein the storage-maintenance unit: constructs thehash table that includes the information about the mobile devicesroaming within the wireless network; and indexes the informationincluded in the table by Media Access Control (MAC) addresses that eachcorrespond to a different mobile device roaming within the wirelessnetwork.
 13. The network device of claim 12, wherein thestorage-maintenance unit further: receives, from the specific AP, one ormore notifications indicating that one or more of the mobile devicesroaming within the wireless network have recently visited the specificAP; and updating the information included in the table based at least inpart on the notifications received from the specific AP.
 14. The networkdevice of claim 12, wherein the storage-maintenance unit further:receives, from another AP within the wireless network, a notificationindicating that the mobile device has recently visited the other AP; andupdating the information included in the table based at least in part onthe notification indicating that the mobile device has recently visitedthe other AP.
 15. The network device of claim 12, wherein theinformation about the mobile devices comprises information thatidentifies a set of APs whose probabilities of the mobile devicevisiting next are above the certain threshold.
 16. The network device ofclaim 15, wherein the information about the mobile devices furthercomprises information that identifies, for each individual AP within theset of APs: a MAC address of the individual AP; a number of times thatthe mobile device has visited the individual AP; a probability that theindividual AP is the next AP visited by the mobile device; and an agingtimer that represents an amount of time since the mobile device lastvisited the individual AP.
 17. The network device of claim 16, whereinthe storage-maintenance unit: determines, based at least in part on theaging timer, that the mobile device has not visited the individual APwithin a certain amount of time; and removes an entry corresponding tothe individual AP from the information in response to determining thatthe mobile device has not visited the individual AP within the certainamount of time.
 18. The network device of claim 16, wherein theAP-prediction unit: detecting, based at least in part on the agingtimer, an increase in the amount of time since the mobile device lastvisited the individual AP; and decrementing the probability that theindividual AP is the next AP visited by the mobile device due at leastin part to the increase in the amount of time since the mobile devicelast visited the individual AP.
 19. The network device of claim 11,wherein the AP-prediction unit determines the number of times that themobile device has visited the specific AP by determining a number oftimes that the mobile device has established a network connectionthrough the specific AP.
 20. A method comprising: determining a numberof times that a mobile device has visited a specific Access Point (AP)within a wireless network; generating, based at least in part on thenumber of times that the mobile device has visited the specific AP, aprobability that the specific AP is the next AP visited by the mobiledevice; determining that the probability is above a certain threshold;and providing, in response to the determination that the probability isabove the certain threshold, the specific AP with a roaming-sessionprofile that: facilitates transferring a roaming session of the mobiledevice to the specific AP in anticipation of the specific AP being thenext AP visited by the mobile device while roaming within the wirelessnetwork; and enables the specific AP to provide network access to themobile device due at least in part to the mobile device having beenauthenticated previously by an additional AP.